An Overview of the Interdiffusion Studies in Mo-Si and W-Si Systems

Abstract

The growth of phases by reactive diffusion in Mo-Si and W-Si systems are compared. The crystal structures of MSi2 and M5Si3 phases (M = Mo, W) are similar in these two systems. However, the diffusion rates of the components change systematically with a change in the atomic number. Integrated diffusion coefficients in both phases increase with an increasing atomic number of refractory elements i.e. from Mo to W. On the other hand, the ratio of diffusivities of the components decreases. This indicates a relative increase in the diffusion rates of the metal components with increasing atomic number and a difference in defects concentrations in these two systems.